Bump sharp from 0.30.7 to 0.31.0 in /searx/static/themes/simple

Bumps [sharp](https://github.com/lovell/sharp) from 0.30.7 to 0.31.0.
- [Release notes](https://github.com/lovell/sharp/releases)
- [Changelog](https://github.com/lovell/sharp/blob/main/docs/changelog.md)
- [Commits](https://github.com/lovell/sharp/compare/v0.30.7...v0.31.0

)

---
updated-dependencies:
- dependency-name: sharp
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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